diff --git a/platformio.ini b/platformio.ini
index e178230..4c71772 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -15,4 +15,5 @@ platform = atmelavr
 board = uno
 framework = arduino
 lib_deps =
-     adafruit/Adafruit BME280 Library @ ^2.1.2
+     ; adafruit/Adafruit BME280 Library @ ^2.1.2
+     sparkfun/SparkFun HTU21D Humidity and Temperature Sensor Breakout @ ^1.1.3
diff --git a/src/main.cpp b/src/main.cpp
index 7c45941..13fd5f7 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,6 +1,6 @@
 #include <Arduino.h>
 #include <MQ135.h>
-#include <Adafruit_BME280.h>
+#include <SparkFunHTU21D.h>
 
 #define PIN_MQ135 A0
 #define PIN_NOISE 2
@@ -12,26 +12,29 @@
 #define PIN_LED_RED2 8
 
 MQ135 co2_sensor(PIN_MQ135);
-Adafruit_BME280 bme;
+HTU21D envSensor;
 
 void setup() {
   Serial.begin(9600);
 
-  // if (!bme.begin(0x76)) {
-  //   Serial.println(F("Could not find a valid BME280 sensor, check wiring!"));
-  // }
+  co2_sensor.setR0(200);
+
+  envSensor.begin();
 }
 
 void loop() {
-  // float temp = bme.readTemperature();
-  // float humidity = bme.readHumidity();
+  float temp = envSensor.readTemperature();
+  float humidity = envSensor.readHumidity();
 
-  // float r0 = co2_sensor.getCorrectedR0(temp, humidity);
+  float r0c = co2_sensor.getCorrectedR0(temp, humidity);
   float in = analogRead(PIN_MQ135);
   double v = co2_sensor.getVoltage();
   double r = co2_sensor.getResistance();
   float r0 = co2_sensor.getR0();
 
+  double co2 = co2_sensor.getCO2();
+  double co2c = co2_sensor.getCorrectedCO2(temp, humidity);
+
   Serial.print("Analog Read: ");
   Serial.println(in);
   Serial.print("Voltage: ");
@@ -39,12 +42,19 @@ void loop() {
   Serial.print("Resistance: ");
   Serial.println(r);
 
-  // Serial.print("Temperature: ");
-  // Serial.println(temp);
-  // Serial.print("Humidity: ");
-  // Serial.println(humidity);
   Serial.print("R0: ");
   Serial.println(r0);
+  Serial.print("Temperature: ");
+  Serial.println(temp);
+  Serial.print("Humidity: ");
+  Serial.println(humidity);
+  Serial.print("R0 Corrected: ");
+  Serial.println(r0c);
+
+  Serial.print("CO2: ");
+  Serial.println(co2);
+  Serial.print("CO2 Corrected: ");
+  Serial.println(co2c);
 
   Serial.println("-----------------------------");